Genotypic and phenotypic characteristics of adults with cystic fibrosis in the Republic of Kazakhstan

Cystic fibrosis (CF) is a hereditary multisystem disorder characterized by progressive damage to the respiratory and gastrointestinal systems. Data on adult patients with CF are limited in the Republic of Kazakhstan (RK), and the lack of a national registry makes it difficult to evaluate the clinical and functional characteristics of this population.

The aim was to present the genotypic and phenotypic characteristics of adult patients with CF in the RK.

Methods. Data from 29 adult patients (18 years and older) with a confirmed diagnosis of CF from various regions of the RK for 2024 were analyzed. Clinical, anthropometric, functional, laboratory, microbiological, and molecular genetic parameters were assessed according to European Cystic Fibrosis Society Patient Registry (ECFSPR) protocols.

Results. The mean age of patients was 23.3 years, and the median age at diagnosis was 9 years. BMI was below the target values (19.17 kg/m²). Exocrine pancreatic insufficiency was detected in 80% of patients (fecal elastase < 200 pg/g), predominantly in those with “severe” CFTR genotypes. The F508del mutation was detected in 45% of alleles. “Severe” genotypes, associated with earlier diagnosis, low pancreatic function, and high sweat chloride levels, were identified in 72.4% of patients. The mean FEV₁ value was 60.7% predicted, with 35.8% of patients experiencing severe or very severe airflow obstruction. Chronic Pseudomonas aeruginosa infection was detected in 69% of patients. Initiation of CFTR modulator therapy was associated with a reduction in the exacerbation frequency and the need for intravenous antibiotic therapy in most patients.

Conclusion. Adult patients with CF in Kazakhstan are characterized by late diagnosis, decreased nutritional status and respiratory function, and a high rate of exacerbations. Data integration into the ECFSPR is a key step toward developing systemic care and optimizing CF therapy in the country.

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